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arXiv · 1909.10211

Facets of congruence distributivity in Goursat categories

Marino Gran·Diana Rodelo·Idriss Tchoffo Nguefeu
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Abstract

We give new characterisations of regular Mal'tsev categories with distributive lattice of equivalence relations through variations of the so-called Triangular Lemma and Trapezoid Lemma in universal algebra. We then give new characterisations of equivalence distributive Goursat categories (which extend $3$-permutable varieties) through variations of the Triangular and Trapezoid Lemmas involving reflexive and positive relations.

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Marino Gran, Diana Rodelo, Idriss Tchoffo Nguefeu. 2019-09-23. Facets of congruence distributivity in Goursat categories. https://doi.org/10.1016/j.jpaa.2020.106380

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